Python中a is b和a==b的区别？

# 以下用于示例 a == b 用法

>>> a = 1 # a, b 数值类型

>>> b = 1

>>> a == b

True

>>> a = 'zhaoxuan'# a,b 字符串类型

>>> b = 'zhaoxuan'

>>> a == b

True

>>> a = [1, 2]# a,b 列表类型

>>> b = [1, 2]

>>> a == b

True

>>> a = 1 # a, b 数值类型

>>> b = 2

>>> a == b

False

>>> a = 'hello'# a,b 字符串类型

>>> b = 'world'

>>> a == b

False

>>> a = [1, 2]# a,b 列表类型

>>> b = [1, 3]

>>> a == b

False

# 以下用于示意 a is b 用法:

>>> a = -5# a, b 数值类型

>>> b = -5

>>> a is b

True

>>> a = -6

>>> b = -6

>>> a is b

False

>>> a = 256

>>> b = 256

>>> a is b

True

>>> a = 257

>>> b = 257

>>> a is b

False

>>> b = 'zhaoxuan'# a, b 字符串类型

>>> a = 'zhaoxuan'

>>> a is b

True# 简单字符串可用

>>> id(a)

42111997

>>> id(b)

42111997

>>> a = 'wo shi zhao xuan'

>>> b = 'wo shi zhao xuan'

>>> a is b

False# 复杂字符串不可用

>>> id(a)

2146074255200

>>> id(b)

2146074255272

>>> a = (1,2,3) # a, b 元组类型

>>> b = (1,2,3)

>>> a is b

False

>>> id(a)

2146074256320

>>> id(b)

2146074256378

>>> a = [1,2,3]  #a,b list类型

>>> b = [1,2,3]

>>> a is b

False

>>> a = {'a':1,'b':2} #a,b dict类型

>>> b = {'a':1,'b':2}

>>> a is b

False

>>> a = set([1,2,3])#a,b set类型

>>> b = set([1,2,3])

>>> a is b

False

>>> id(a)

2146074299258

>>> id(b)

2146074299236